Safety device for water turbines



Oct. 21 i924. 1,512,114

. c. LEFFLER I SAFETY DEVICE FOR WATER TURBINES Fil ed Aug. 26. 1921 2 Sheets-Shae). 1

1,512,114 C. LEFFLER SAFETY DEVICE FUR WATER TURBINES Filed Aug. 26. I 2 i941.-

Sheets-Sheet. 2

Patented Oct. 21, 1924.

UNITED STATES CHRISTOPH LEFFLER, OF BRUNSWICK, GERMANY.

SAFETY DEVICE FOR WATER TURBI NES.

Application filed August 26, 1921.

T 0 all whoma't may concern:

Be it known that I, CI-IRIST'OPI-I Lnrrnnn, a citizen of Germany, residing at Brunswick, Germany, have invented certain new and useful Improvements in Safety Devices for Water Turbines (for which I have filed applications in Germany, June 22, 1920; September 30, 1920; October 5, 1920, and January 2 1, 1921; Norway, June 21, 1921; Austria, June 18, 1921; Switzerland, June 11, 1921; Netherlands, June 21, 1921; France, June 15, 1921; England, June 20 and 23, 1921; Italy, June 1 1, 1921), of which the following is a specification.

My invention relates to water-turbines and more especially to a safety device for turbines working in conjunction with booster engines.

In order to provide for peak loads these engines are regulated, while a regulation of the turbines can be dispensed with. The turbines must only be protected against meing in consequence of short-circuit or breaking of the belt or against an excessive number of rotations. For this purpose acentrifugal governor is employed which when the driven shaft exceeds a predetermined number of revolutions operates a gearing for closing the gate apparatus of the turbine.

On the one hand the gearing for closing the gate apparatus of the turbine must re main in operation until the distribution apparatus is closed and on the other hand an exceeding of the closing position of the gate apparatus must be prevented wit-h certainty. To attain this result, I provide between the gear for closing the gate apparatus of the turbine and the closing device of the turbine a coupling or clutch which is thrown out of engagement by the closing gear shortly before the closing movement has been accomplished.

In the drawings afiixed to this specification and forming part thereof different embodiment-s of my invention are illustrated by way of example. In the drawings- Fig. 1 is a diagrammatic view of one form,

Fig. 2 is a diagrammatic elevation and Fig. 3 is a plan of a. modification.

Fig. 4 is a diagram of a third and Fig. 5 a similar view of a fourth modification.

Similar pa'rts are indicated by the same letters of reference throughout the figures of the drawings.

Referring to Fig. 1, the turbine a; drives Serial No. 495,558.

the shaft 6 which, by aid of a ulley c and belt, drives a dynamo or the like not shown). Mounted on the shaft 6 is another pulley (Z which by means of a belt d drives a centrifugal or pendulum governor g. If the shaft Z) exceeds its permissible number of revolutions the sleeve 2? of the governor 9 moves a bell crank lever to, against the free end a of which there rests a trip lever 41 actuated by a weight 'v, in such a manner that the lever o is released and tilts over. During the downward motion of the lever a pin 41 on the lever engages a guide slot w arranged upon a belt fork 00. The prongs m of this fork hold between them the belt al driving the pendulum governor As the guide slot 10 is disposed at an angle relatively to the path of the pin W, the belt fork is moved in the direction of the arrow and held inthis position. In this manner the belt 03 is moved from the pulley r onto a pulley S1 fixed on the shaft f. The rotation of this shaft is transmitted by means of the spur wheel-s ii, a to a counter shaft 70 which carries a worm Z meshing'with a segment m which controls the gate apparatus of the turbine at. Hereby the water supply of the turbine is cut off and the turbine a together with the shaft 6 and the pulley 0 are stopped. The pendulum governor g and the pulley shifting device may be replaced by a centrifugal device and a shifting device of some other kind.

In order that the inertia of the revolving parts of the turbine and the dynamo shall not cause the motion of the counter shaft 7c and the segment at controlling the turbine to continue after the supply of water to the turbine has been stopped, the segment or is connected by a link a with the clutch 0, which immediately before the segment m has reached its closing position disengages the two portions of the counter shaft 70, so that the segment m is no longer driven by the spur wheel Z.

A hand wheel p on shaft 70 serves to start the turbine a again, the hand wheel turning the worm Z and the controlling segment back into their original positions and reopening the gate apparatus of the turbine, so that the turbine is again supplied with water.

The clutch or coupling 0 may be replaced by the device shown in Figs. 2 and 3. In this construction a rope t is provided between the shafts and 70, said rope being attached to the shaft f at one end while the other endcarries a hook or an eye which can be hooked over projections on the circumference of a disc a mounted upon the shaft is, and is slung around this d1sc. When the shaft f is driven, the shaft is is rotated ernor, after having performed the revoluscrew thread tions required for closing the turbine, is free to automatically disengage itself, as illustrated by way of example in Fig. 4.

Instead of the coupling 0 operated in Fig. 1 by the segment m, the link 7t and the guided fork for interrupting the drive after the closing movement has been accomplished, a screw device may be provided which shifts the belt. This device consists of left-handed f provided on the counter shaft 7 and a nut f which carries a bent arm f abutting against the belt shifter.

As soon as the shaft 7 starts rotating, the nut f together with its arm f is moved towards the right and the arm moves the belt shifter w back into its initial position so that the belt 6Z1 again moves back from the pulleys a onto the pulley r When the closing position has been reached by the segment m,

the drive has meanwhile automatically disengaged itself.

In order that the pin 0 of the trip lever 0 may not obstruct the return of the belt shifter, the guide slot w may at its lower 3 end branch off horizontally at w and the pin '0 may drop out at the end after having traversed this horizontal slot. The nut 7 may be returned to its starting position and.

the turbine admission apparatus may be opened by turning the hand wheel p.

In the modification disclosed in Fig. 5, instead of a coupling which is disengaged by the segment m, a coupling automatically unscrewing itself is provided. The wheel 2' driven by a spur wheel h on the counter shaft f" is provided with internal screw thread in its hub 71 and screwed upon a stationary screw threaded bolt k Claws 0 on the hub i engage corresponding recesses 0 in a head on the worm shaft 70.

As soon as the spur wheel h'begins to rotate and the worm shaft is and the segment m are rotated by the wheel 1; and the coupling 0, the wheel 2' moves along the screw threaded spindle k in the direction of the arrow y until the claw coupling 0, 0 is disengaged and further rotation of the worm shaft k and the segment on is stopped.

The disengagement of the drive, after the necessary revolutions of the worm shaft or the like for shutting off the turbine have been performed, may also be accomplished by the aid of an electromotor, which switches itself out automatically.

, I wish it tobe understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

I claim:

1. In a water turbine a safety device comprising a gate apparatus, means for closing said apparatus, means influenced by said turbine for driving said closing means, a centrifugal device operatively connected with said turbine and a weighted lever adapted to bring said driving means in operative connection. with said closing means and to be operated by said centrifugal device, when a predetermined'number of revolutions is exceeded and means, influenced by the closing means, for interrupting the operative connection between said driving means and said closing means before the gate prising a gate apparatus, means 'for closing said apparatus, means influenced by the said turbine for driving said closing means, a centrifugal device operatively connected with said turbine, abelt for transmitting power from the turbine to said closing means, a belt shifter, a weighted lever adapted when a predetermined number of revolutions is exceeded to shift saidbelt shifter, a cou ling between said driving'means and said 0 osing means and means, influenced by said closing means, for disengaging said.

coupling before said gate apparatus is closed. V

3. In a water turbine a safety device comprising a gate apparatus, means for closing said apparatus, means influenced by the said turbine for driving said closing means, a centrifugal device operativelyv connected with said turbine, a belt for transmitting power from the turbine to said closing. means, a belt shifter, a weighted lever controlled by said centrifugal device adapted when a predetermined number of revolutions is exceeded to shift said belt shifter, a coupling between said driving means and said closing means and means, influenced by said closing means, for moving said belt shifter back so as to interrupt the operative connection between said driving means and said closing meansbefore said gate apparatus is closed. f p 7 4. In a water turbine a safety device comprising a gate apparatus, means for closing said apparatus, means influenced by'the said turbine for driving said closing means, a

centrifugal device operatively connected with said turbine, a belt for transmitting power from' the turbine to said closing;

means, a belt shifter, a weighted lever controlled by said centrifugal device adapted When a predetermined number of revolutions closing means before said gate apparatus is is exceeded to shift said belt shifter, a couclosed. 1 pling between said driving means and said In testimony whereof I afiiX my signaclosing means, a Wandering nut and means, ture.

influenced by said closing means, for rotat- CHRISTOPH LEFFLER. ing said nut for moving said belt shifter Witnesses: back so as to interruptthe operative connec- WILLI FAHN,

tion between said driving means and said HILDE Brnnrrz. 

